Retaining means for excavating teeth



S p 1969 E. w. LEFFINGWELL 3,469,332

RETAINING MEANS FOR EXCAVATING TEETH Filed Sept. 28. 1967 4 Sheets-Sheet l INVENTOR. Earl W Leffingwell His Attorneys 0, 1969 E. w. LEFFINGWELL 3,469,332

RETAINING MEANS FOR EXCAVATING TEETH 4 Sheets-Sheet 2 Filed Sept. 28, 1967 ilJ INVENTOR. Earl W Leffingwell His Attorneys P 1969 E. w. LEFFINGWELL 3,469,332

RETAINING MEANS FOR EXCAVATING TEETH Filed Sept. 28, 1967 4 Sheets-Sheet 5 INVENTOR.

Earl W Leffin welt His Attorneys Sept. 30, 1969 w, L F N LL 3,469,332

RETAINING MEANS FOR EXCAVATING TEETH Filed Sept. 28, 1967 4 Sheets-Sheet 4.

INVENTOR, Earl W. Leffingwell His Attorneys United States Patent M US. Cl. 37142 8 Claims ABSTRACT OF THE DISCLOSURE A locking means for releeasably reetaining an excavating tooth in a socket mounted on earth digging equipment wherein the tooth is formed with a hardened distal portion for cutting and a proximal end having a malleable portion which is deformable to interlock with the socket.

BACKGROUND OF THE INVENTION The present application is a continuation-in-part of my prior copending US. patent application, Ser. No. 640,736 filed May 23, 1967, now abandoned.

This invention pertains to excavating teeth and in par.- ticular to a method for releasably attaching the teeth in their sockets.

The prior art devices show a variety of means for attaching the teeth to the holders. Some teeth are attached by pins driven through the tooth and into the holder. These are unsatisfactory as the pins drop out and the tooth is lost or the pin jams and it is dilficult to remove the worn tooth. Recent work has been done in jamming resilient inserts between the root of the tooth and the inside wall of the insert. This method makes removal unnecessarily difficult. Installation is impossible without the special small resilient inserts which are easily lost or misplaced.

' SUMMARY The gist of the invention is the provisionof a malleable portion on the proximal end of the tooth which is bent over a wall provided on the socket or is deformed by a cam face as the tooth is driven into the socket. On full insertion, the finger interlocks with a depending socket tongue or second wall to prevent removal of the tooth.

An object of the invention is to provide a simple method of securely removably attaching the tooth to the socket without pins, resilient inserts or other separate parts which can be misplaced or lost.

Another object is to provide a simple and easy means of removing the worn tooth.

Still another object is to provide a locking means which permits fast installation, is rugged, and does not add to the cost of the tooth and socket.

A final object is to provide a self-locking means adaptable to substantially all the major tooth and socket combinations.

BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 1 is a plan view of the device constructed in accordance with the present invention.

FIGURE 2 is a cross-sectional view taken substantially along the line 22 of FIGURE 1 showing the tooth in position and prior to positioning.

FIGURE 3 is a side view of another form of the device.

FIGURE 4 is a top plan view of the device shown in FIGURE 3.

FIGURE 5 is a plan view of still another form of the invention.

FIGURE 6 is a side view of the device shown in 3,469,332 Patented Sept. 30, 1969 FIGURE 5 taken substantially along the line 66 of FIGURE 5 showing portions in cross-section.

FIGURE 7 is a plan view of another form of the invention.

FIGURE 8 is a side view of the invention shown in FIGURE 7 with portions in cross section taken substantially along the line 8-8 of FIGURE 7.

FIGURE 9 is a plan view of still another form of the invention.

FIGURE 10 is a side view of the invention shown in FIGURE 9 with portions in cross section taken substantially along line 1010 of FIGURE 9.

FIGURE 11 is a plan view of a still further form of the invention.

FIGURE 12 is a side view of the device shown in FIGURE 11 with portions in cross section taken substantially along line 1212 of FIGURE 11.

FIGURE 13 is a plan view of a further form of the invention.

FIGURE 14 is a side View of the device shown in FIGURE 13 with portions in cross section along the line 14-14 of FIGURE 13.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The combination of the present invention consists of a tooth 1 having a distal portion 3 hardened for cutting and a proximal end 5 having a wall formed for resisting all lateral forces and for resisting longitudinal forces in one direction and a deformable malleable finger 7 projecting generally axially from the proximal end; and a socket member 9 formed with a first wall 11 in registration with the inserted tooth wall 5, the socket being formed with a cam wall 13 positioned to bend and permanently deform the finger out of axial alignment when the tooth is driven into the socket and the socket being formed with a second wall 15 adjacent the cam wall defining a non-linear passage to interlock with the deformed finger to resist longitudinal removal of the tooth.

Finger 7 may be welded or attached to face 17 of the tooth in any of various ways, but is most inexpensively formed by casting it as an appendage of the tooth itself or merely leaving a portion of the flash appended to the tooth which results from forging the tooth from bar stock. Flash is further defined as all that excess metal which flows over the flash line of the die in the forging process and is normally cut away from the formed tooth. In this invention the cutter is shaped to leave a portion of the flash appended to the formed tooth on the proximal end while cutting away the rest of the flash. The

. particular cross-sectional shape of the appendage is unimportant and may be circular, square or other shape. The cross-sectional area need only be sufiicient to give the required strength to prevent removal of the tooth and must be small enough to permit bending of the finger against the cam surface 13 by driving the tooth with a hammer or other implement.

The shape and length of the tooth wall 5 and the registering socket wall 11 do not form a part of this invention except that they must carry the lateral forces that are exerted between the socket and the tooth. Cam wall 13 is placed in alignment with socket wall 11 so as to engage the distal end of the finger and bend the finger out of alignment with the longitudinal axis of the tooth as the tooth is driven into the socket. The second socket Wall 15 is positioned adjacent the cam wall 13 so as to engage the bent finger after it has been driven into the socket and prevent longitudinal removal 'of the tooth. Longitudinal forces driving the tooth into the socket are resisted either by tapering walls 11 or by providing a cam surface v19 which engages edge 21 of the proximal portion of the tooth driving tooth edge 22 against socket 7 wall portion 23.

Since forging the teeth from bar round stock hardens the teeth including the appendages later used for interlocking purposes, these portions of the teeth or appendages must be annealed or drawn as the process is referred to in the trade. This annealing or drawing renders the portion or appendage malleable so that it can be bent or deformed by the cam or by a hammer or other implement used to bend the appendage.

While holding the tooth in the socket is a major problem, a related problem is the ability to remove the tooth when its cutting edge 25 has been blunted or broken. Socket 9 is formed with a passage which communicates with an external wall 27 of the socket providing access to an elongated tool for driving the tooth from the socket member.

The tooth shown in FIGURES 1 through 3 has an elongated shank which may be generally designated by the number 5 and the socket member 9 has a socket wall generally defined by the number 11 which surrounds the side wall of the tooth shank.

The invention is shown in a dilferent form of tooth in FIGURES 3 and 4. The combination consists of a tooth 31 having a distal portion 33 for cutting and a proximal end 35 having a wall formed for resisting all lateral and for resisting longitudinal forces in one direction and a deformable finger 37 projecting generally axially from the proximal end; and a socket member 39 formed with a first wall 41 in registration with the inserted tooth wall here identified by number 35, the socket being formed with a cam wall 43 positioned to bend and permanently deform the finger out of axial alignment when the tooth is driven into the socket and the socket being formed with a second wall 45 adjacent the cam wall defining a non-linear passage to interlock with the deformed finger to resist longitudinal removal of the tooth.

As can be seen in FIGURES 3 and 4, the proximal tooth end is formed with a pair of depending prongs-35 and 36, and the socket is formed with a web 40 for registration between the prongs.

FIGURES 5 and 6 show the invention in still another form of tooth and holder. In this form the combination consists of a tooth 51 having a distal portion 53 for cutting and a proximal end 55 having a wall formed for resisting all lateral and for resisting longitudinal forces in one direction and a deformable finger 57 projecting generally axially from the proximal end; and a socket member 59 formed with a first wall 61 in registration with the inserted tooth wall, the socket being formed with a cam wall 63 positioned to bend and permanently deform the finger out of axial alignment when the tooth is driven into the socket and the socket being formed with a second wall 65 adjacent the cam wall defining a non-linear passage to interlock with the deformed finger to resist longitudinal removal of the tooth.

To facilitate removal of the worn tooth, the holder shown in FIGURE 1 is formed with a second passage 67 communicating with the inserted proximal end 5 of the tooth. In FIGURE 5 the passage may be inserted through an opening at a point generally indicated by the arrow 69.

It has been found that insertion of the tooth is facilitated if the finger attached to the proximal end of the tooth is formed with an enlarged section thereby presenting a smooth rounded surface on the cam wall face. In FIGURES 1 and 2 this enlargement is shown as spherical area 8; in FIGURES 3 and 4 it is rounded area 38; and in FIGURES 5 and 6 as rounded area 58.

The interlocking of the finger to prevent removal of the tooth is improved by shaping the first and second walls of the socket member so that they cooperate to bend the finger to a shape in which the curvature is greater at the distal end than at the proximal end and the second 4 wall (see specifically wall 15 of FIGURE 2) projects toward the first cam wall 18 so as to interlock with enlarged end '8 of the finger and the crook of the curved finger.

The direction that the finger is bent from the longitudinal axis of the tooth is unimportant. Note that in FIGURE 2 the finger is curved upwardly in relation to the tooth whereas in FIGURE 5 the finger is bent in a direction transverse to the longitudinal axis.

In operation, the teeth shown in FIGURES 1 through 6 are inserted into their respective sockets until the fingers strike the cam face walls. A hammer or other instrument is then used to force the teeth further into their respective sockets until the fingers riding along the cam face walls bend and curve around the adjacent tongues until it is impossible to withdraw the teeth from the sockets.

To remove a tooth from its socket a chisel or other elongated tool is inserted into the passage until it is in contact with the proximal end of the tooth. A hammer or other means can be used to drive the tooth out of the socket.

FIGURES 7 and 8 show another form of tooth and socket holder embodying the present invention. The digging tooth 71 has a distal portion 72 hardened for cutting and a proximal end 73 having a malleable portion 74 having a first position for inserting and a second deformed position (shown in FIGURE 8) for interlocking with the socket member 75. In this figure it can be seen that the malleable portion need not be a long narrow tongue but indeed can be a projection extending the width of the tooth. This configuration of the projection is well adapted, but of course not limited to, sockets which have openings 76-and 77. Here the malleable portion 74 is in registration with the openings and can be easily deformed by inserting a tool into the opening 76 and driving the malleable portion 74 partially into the opening 77 where surface 79 of the appendage interlocks with wall portion 78 of the opening 7 7.

Still another form of the device is shown in FIGURES 9 and 10. The tooth is known as the Jiffy tooth and consists of a distal end 81 and a proximal end 82. A single protrusion 83 which is either formed by forging along with the tooth or from the flash is annealed and after insertion is bent over wall 84 of the socket 85. Plate 86 of the socket member is generally attached by welding in the field.

The tooth and holder shown in FIGURES l1 and 12 is still another form of the invention consisting of a distal end 88, a proximal end 89 and a malleable tongue member 90 which may be either forged, formed from the flash or attached by other methods as by welding. The gizember is bent over wall 91 formed in socket member Still another form of the invention is shown in FIG- URES 13 and 14. This alternate form consists of a hardened distal end 94, and a pair of protruding members 95 and 96, connected to proximal end 97. In FIGURE 14 the dotted lines show the inserted position of the appendage 95 and the solid lines show the deformed interlocking position. The appendage is interlocked with wall 98 of the socket member 99 as by bending with a hammer or other tool. The appendages may be forged as part of the tooth and annealed, or formed from the flash and then annealed. Attachment could be by bolting, welding or any other standard method of attachment.

It is to be understood that there are a great number of different kinds of teeth and holders in which the teeth can be attached by the principles of this invention. All that needs to be done is to vary the shape or placement of the malleable appendage. The teeth and holders represented in the drawing are only by way of example. It is to be understood that the appendage or tongue of metal protruding from the tooth need not be on the end but could be on the side, top, or bottom to accommodate a particular type of tooth and socket.

I claim:

1. A forged digging tooth having a distal portion hardened for cutting and a proximal end having a malleable portion formed from the flash when said tooth is forged and said malleable portion having a first position for inserting and a second deformed position for interlocking, a socket member formed with a first passage for insertion of the proximal end of said tooth therein, said socket being formed with a second passage transversely intersecting said first passage and having one end communicating with an outside wall of said socket for insertion of a tool therein, and said malleable portion extending into said intersection and interlocking with said socket upon being driven into said second passage.

2. A forged digging tooth having a distal portion hardened for cutting and a proximal end having a malleable portion formed from the flash when said tooth is forged and said malleable portion having a first position for inserting and a second deformed position for interlocking, said proximal portion of said tooth is formed with a wall for resisting all lateral and for resisting longitudinal forces in one direction, and a socket member formed with a first wall in registration with said inserted tooth wall, said socket being formed with a second wall positioned to interlock with said malleable portion and to resist longitudinal removal of said tooth, and said socket is formed with a cam wall positioned to bend and permanently deform said malleable portion out of axial alignment and into interlocking engagement with said socket second wall when said tooth is driven into said socket thereby resisting longitudinal removal of said tooth.

3. A digging tooth as described in claim 2 wherein said cam wall and second wall form a non-linear passage and said passage communicates with an external wall of said socket providing access to an elongated tool for driving said tooth from said socket member.

4. A digging tooth having a distal portion hardened for cutting and a proximal end having a malleable deformable portion projecting from said proximal end, said malleable portion having a first position for inserting and a second deformed portion for interlocking and a socket member formed with a first passage for insertion of the proximal end of said tooth therein, said socket being formed with a second passage transversely intersecting said first passage and having one end communicating with an outside wall of said socket for insertion of a tool therein, said member extending into said intersection and interlocking with said socket upon being driven into said second passage.

5. A digging tooth as described in claim 4 wherein said socket is formed with a cam wall positioned to bend and permanently deform said deformable member out of axial alignment and into interlocking engagement with said socket second wall when said tooth is driven into said socket thereby resisting longitudinal removal of said tooth.

6. A method for making a digging tooth comprising the steps of: forging a tooth from metal stock, forming a hardened distal digging end and a proximal end for insertion into a socket member, removing the flash formed by said forging step except for a portion on said proximal end forming a protrusion; and annealing said protruding portion thereby rendering said portion malleable.

7. A method for attaching a digging tooth to a socket member including the steps of: selecting a tooth having a hardened distal digging end and a proximal end having a malleable portion, selecting a socket member having a second wall and cam wall positioned to bend and permanently deform said malleable portion out of axial alignment and into interlocking engagement with said second wall of said socket member, and driving said tooth into said socket with a force sufiicient to cause said malleable portion to engage and be deformed by said cam wall into interlocking engagement with said second wall.

8. A method for attaching a digging tooth to a socket member including the steps of: selecting a tooth having a hardened distal digging end and a proximal end having a malleable mem-ber protruding therefrom, said member having a first position and a second deformed position; selecting a socket member having a cam wall positioned to bend and permanently deform said mallea'ble member out of axial alignment and a second wall positioned to interlock with said deformed member; and driving said tooth into said socket with a force suflicient to deform said malleable member into interlocking engagement with said socket.

References Cited UNITED STATES PATENTS 352,004 11/1886 Richards 143-153 450,811 4/ 1891 Junquera 279-104 XR 565,910 8/1896 Maynard 279-104 XR 751,902 2/1904 Dodge 279-104 XR 1,178,209 4/1916 Benjamin 279-104 (R 1,433,206 10/1922 Hojnowski 279-104 XR 2,124,230 7/1938 Hosmer et a1. 37-142 2,238,081 4/ 1941 Soberanes 37-142 72,305,653 12/1942 Ward 37-142 2,603,009 7/1952 Smith 37-142 2,916,275 12/1959 Bruestle et al. 299-92 2,940,191 6/1960 Askue 37-142 EDGAR S. BURR, Primary Examiner US. Cl. X.R. 299-91 

